Designing a 4-20mA analog input board to bring gas sensor data onto a client's control system
Challenge
A client building a gas-detection system needed a way to bring standard industrial 4-20mA current-loop gas sensors onto their own control platform without designing and validating the sensor-interfacing electronics themselves. They needed multiple sensor channels, conversion accurate enough to trust the readings for gas-concentration decisions, and a way for the board to talk to the rest of their system without pulling them into a new custom communication protocol.
Solution
We designed a dedicated analog input board around a 16-bit ADS8344 ADC (Texas Instruments) feeding four independent 4-20mA current-loop input channels, so up to four gas sensors - or any other 4-20mA industrial transmitter - can be read simultaneously with enough resolution to resolve small changes in gas concentration reliably. An STM32C031C6T6 microcontroller drives the ADC, handles channel sequencing and conversion, and exposes the readings to the client's own master controller over I2C - a simple, widely supported bus that let the client integrate the board into their existing system architecture without adopting a new protocol. We laid the board out in Altium Designer as a compact, self-contained module with clearly labeled inputs and a dedicated connector footprint, so it drops into the client's enclosure as a discrete sensor-interface stage rather than a proof of concept the client would need to re-engineer for production.
Results
The result is a purpose-built bridge between industrial 4-20mA gas sensors and the client's control platform: four channels of accurate, 16-bit analog-to-digital conversion delivered over a simple I2C link the client's own system already knew how to talk to. Instead of designing, validating, and re-spinning their own current-loop input circuitry, the client got a proven, drop-in board that let their engineering effort stay focused on the gas-detection logic itself rather than the analog front end underneath it.
Kick-start your project
Get in touch with our team to discuss your business needs and see how we can help with a project like this one.